What I've come up with is a system of making up your character as you go. At times the game will ask you questions about your player's past. The answer (or lack of an answer) will actually drive the story in different directions as the game builds a profile, passively, about your character. Different points in the game will behave differently based on the profile the computer builds.
For instance, A medical form may ask for your gender. That's pretty easy, from then on the game can refer to you as a male, female, or something of the player's choosing. More tricky would be on that same form, it may ask you questions about medical ailments your family has a history of. If you give an answer, even a crazy answer, the machine could ignore that. But if you mark "I don't know", that could open up to the computer the idea that your character is an orphan. An interaction with a Villain later might offer you a speech option that a non-orphan wouldn't have access to, that leads to a different outcome.
At the same time, providing inconsistent answers could flag your character as somewhat shifty. NPCs may not trust you. Nothing specific, just a gut feeling. Unless you give the same NPC two different answers. Then they will DEFINITELY not trust you.
For the moment, I'm building the game out with a choose your own adventure style of conversations. In The Epic of Gilgamesh I plan on having intelligent agent chatbots manage conversations. But this game is designed to be something simpler I can actually finish in my spare time. More of a playable technology demonstrator than final product. (But of course the quality of a "demonstrator" from me tends to be more mature than most people's "Version 3" of a finished product.)
If I can keep the game state small enough, I could even create an online playable version. But for now, I think I'm going to create a downloadable web server that runs on the player's computer. Sort of like a game console. The game itself will be a zip file that is dragged onto game (like loading a cartridge.) Game saves will be be files that players can name and keep on their computer. (And back up, share, etc.)
So first part of the project here is adapting the Gilgamesh engine to be just that web server, and Identify the knockouts needed for any old game to layer itself on top. More on this as I figure it out.
The takeaway is that once I DO figure that out I plan on publishing those specifications and APIs for anyone who wants to use the engine to develop their own game. Being web based, there is no reason it couldn't also provide graphics and otherwise compute with the likes of RPG maker and Ren'Py.